On average, listings lease in the $10's per square foot per year. The Ada County submarket is going through a decline in rates. In the last 3 months, the median rate fell $1 per sqft per year. That's a 6% decrease in rent.
In the last 90 days, 290 listings have been posted online, so you'll want to check back regularly for new listings. About 4% of the available space in the Ada County are subleases, so you will probably have to focus your search on direct office leases. There aren't many listings below 2,000 square feet posted, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 2,020 sqft. Most buildings in this region are close to 1 stories. Most buildings in this area were built in 1999 and are Class A.